Gas burner



May 9, 1961 G. A. FINLEY ETAL GAS BURNER Filed May 20, 1959'IIlIIIIIIIII/I.

FIG-,3

' JNVENTORS GEORGE A. FINLEY By GEORGE w SPIELER Q A v 4: 4.

AT NEY United States Patent GAS BURNER George A. Finley and George W.Spieler, Aurora, 11]., assignors to Finco, Inc., Aurora, 11]., acorporation of This invention relates to improvements in burners forcombustion of fuel gases which are normally supplied from storage tanksof liquid fuel under pressure.

While other fuels may be used with this burner, it will simplify thediscussion to refer, as an example, to propane which is normallysupplied to the user in a liquid state and stored under pressure. Thetype of burner which we prefer to use belongs in the class of venturitype burners to which the fuel in gaseous form is fed through a smallorifice in the nozzle, under pressure, and as it passes through thethroat of the venturi it inspirates air for combustion and promotes oneof the most efficient :gas and air mixing actions known to. science.When one of these burners is being fed from a liquid propane supply,reduction of pressure on the liquid before it is brought to the burnerpermits vaporization at such lowered pressure, but the heat ofvaporization still must be supplied from some source to convert it fromliquid to gas. The improvement in my device is directed to that purpose,i.e., the efficient and convenient supplying of heat to the liquid fuelso that it may be readily vaporized.

In addition to the above stated general purpose, it is :an object of theinvention to provide an economical fuel pre-heater and one which may beinexpensively mounted and conveniently adjusted to facilitate variationin the amount of pre-heat supplied to the fuel.

Other objects and advantages of the invention will be mentionedhereinafter, or will become apparent from a perusal of thisspecification.

Referring now to the drawing, in which a preferred form of the inventionis illustrated, Figure l is a perspective view of the device shownmounted on a supporting frame of a type suitable for supporting theburner inside of a chamber into which the products of combustion areprojected for admixture with other air.

Figure 2 is a longitudinal, cross-sectional view of the burner andpre-heater. Figure 3 is a side elevation of the pre-heater.

Referring further to the drawing, a conventional venturi burner tube isshown and generally designated as 11, having a throat 12, an inletchamber 13, and an outlet 14. The stationary plate 15, having numerousperforations 16 for the inlet of air, is bolted as shown to theperipheral flange 17. A conventional perforated and rotatable plate 18is secured to the plate 15 by means of screws such as 19, which extendthrough conventional arcuate slots to permit the adjustable plate 19 tobe rotated to vary the total combined aperture of the slots 21 and 16,to vary the proportion of air admitted to the throat of the venturi. Areplaceable spud 22 having an orifice 23 of suitable size is secured tothe stationary plate 15 by means of the lock nut 24 and the gas fuelinlet pipe 25 is secured to the lock nut 24 by means of an elbow 26.This much of the burner is conventional.

The pre-heater consists of a pipe of suitable material such as copper orbronze, or other appropriate material, coiled as shown, mounted somewhatloosely about the outside cylindrical surface of the venturi tube outletend.

2,983,312 Patented May 9, 1 961 ice 2 e 2 The liquid fuel is introducedinto the coil through the pipe 29 and flows around the convolutions suchas 28 of the coil, and eventually emerges in pre-heated conditionthrough the return pipe '27,. A baflle plate 31 is supported in fixedrelation to the pre-heater coils by means of three legs 32, 33 and 34,by welding one end of these legs to the plate 31 and the other end tothe coils as shown.

As an example of how this burner may be mounted axially in a chamber ofcylindrical shape, there is shown a triangular frame consisting of thehorizontal bar 35, two inclined bars 36 and 37, and at the junctures ofthese bars, shoes 38, 39 and 41, which may be secured to the interiorsurfaces of the cylinder by means of bolts, screws, or in any othersuitable manner.

Formed integrally with the venturi tube is a supporting bracket 42,which may be bolted to the bar 35, while a plate 43 may be bolted eitherto the bracket 42 or to the frame bar 35 and adjustably secured to thepipe 29 by means of a U-shaped pipe clamp 44, as shown.

In order that the pre-heating coil may be shifted, the clamp 44 may beloosened sufiiciently to permit the pipe 29 to be slid through it eitherto carry the coils further beyond the mouth of the venturi tube or backtoward the mouth of the venturi tube. It will be recognized that whenthe burner is operating, the flames emitted from the mouth of theventuri tube will impinge against the baflie 31 and in part be deflectedbackwardly, whereby they will supply a large amount of heat directly tothe pre-heater coil.

The exposure of a greater number of coils beyond the end of the venturitube will cause more heat to be imparted to these coils, if it benecessary to raise the preheating temperature of the fuel flowingthrough the preheater coil.

It will be perceived that this pre-heater coil and its associatedbaflie, together with the means of adjusting it longitudinally of theventuri tube, provides an economical structure for the purpose, and onewhich is of the utmost simplicity so far as mounting and adjustabilityis concerned.

The valves which may be employed, such as pressure reduction valves,fuel throttling valves, and any other necessary valves, do not form apart of this invention and are therefore not disclosed.

' purpose we provide that the spark plug 45 be mounted in approximatelythe location shown. Thus the flame formed by the burning fuel mixturewill be beyond the position of the spark plug, which therefore is notsubjected to the temperature and other ill effects of this burningflame.

While a preferred form of the invention is shown, to

illustrate the nature of the invention and the manner of its use, itshould be understood that the invention is susceptible to somemodification without departure from the spirit and scope of theinvention defined in the appended claim.

We claim:

In combination with a gas burner having an elongated burner tube open atits discharge end, a spiral pipe coil the coil axially of the tube toselectively expose different numbers of said convolutions beyond thetube end, means for introducing a liquid fuel into one end of the coil,and means for Withdrawing heated liquid fuel from the other end of thecoil.

References Cited in the file of this patent UNITED STATES PATENTS1,330,635 Kittel Feb. 10, 1920 2,111Q239 Elze Mar. 15, 1938 2,693,229Pagan Nov; 2, 1954' FOREIGN PATENTS 372,727 Great Britain 1932 *Date ofpublication, application became void.

